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* Evusheld retains neutralising activity against Omicron
* REGEN-COV showed diminished potency; active against Delta
* More data on AstraZeneca's Evusheld expected 'very soon'
(Writes through with details on AstraZeneca's drug, background)
By Mrinalika Roy and Pushkala Aripaka
Dec 16 (Reuters) - AstraZeneca and Regeneron
on Thursday reported contrasting data on the
effectiveness of their COVID-19 antibody therapies against the
Omicron variant of the coronavirus, underscoring the major
challenges ahead for drugmakers.
U.S.-based Regeneron said its REGEN-COV therapy, also called
Ronapreve, is less effective against Omicron, though it is still
active against the Delta variant, confirming indications from
lab tests and computer modelling late last month.
Anglo-Swedish rival AstraZeneca, however, said a lab study
found that its antibody cocktail Evusheld retained neutralising
activity against Omicron, the first such data for the treatment.
The new variant has been detected in 77 countries since it
was first identified three weeks ago, fuelling concerns that its
large number of mutations will help it spread faster and evade
protection provided by COVID-19 vaccines and therapeutics.
Earlier this week, German researchers found that COVID-19
therapies developed by Eli Lilly and Regeneron lose most
of their effectiveness when exposed in laboratory tests to
Omicron.
But lab studies this week showed GSK-Vir's
antibody treatment retains neutralizing activity against all
tested coronavirus variants, including Omicron.
The study on Evusheld was done by independent investigators
of the U.S. Food and Drug Administration using so-called
pseudoviruses that feature major coronavirus mutations across
suspicious variants that have emerged so far.
ROAD AHEAD
The researchers found the potency of Evusheld was within the
ranges seen in those previously infected with COVID-19, showing
promise for wide use of the therapy, which is the first
preventative shot other than vaccines against the coronavirus.
AstraZeneca said more analyses of Evusheld against Omicron
are being conducted by the company and third parties, with data
expected "very soon."
Regeneron said REGEN-COV is still active against Delta,
which currently is the most prevalent variant in the United
States.
The European Union's public health body, however, warned on
Wednesday that there was a "very high" risk Omicron would become
dominant in Europe by early next year.
REGEN-COV is currently authorized for use in the United
States to treat people with mild-to-moderate COVID-19 and for
prevention of infection in those exposed to infected
individuals, and others at high risk of exposure.
Evusheld has been granted authorisation to prevent COVID-19
infections in individuals with weak immune systems or a history
of severe side-effects from coronavirus vaccines.
Both treatments belong to a class of medicines called
monoclonal antibodies which mimic natural antibodies in fighting
off infections.
Unlike vaccines, they do not rely on the body to create an
immune response, and can therefore help individuals with weak or
compromised immune systems.
(Reporting by Mrinalika Roy and Pushkala Aripaka in Bengaluru;
Editing by Shailesh Kuber and Paul Simao)
